CONTENTS of Technical Manual (Operational Principle):SECTION 1 GENERAL Group 1 Specification Group 2 Component LayoutSECTION 2 SYSTEM Group 1 Control System Group 2 Hydraulic System Group 3 Electrical SystemSECTION 3 COMPONENT OPERATION Group 1 Pump Device Group 2 Swing Device Group 3 Control Valve Group 4 Pilot Valve Group 5 Travel Device Group 6 Others (Upperstructure)